Capturing Avatar is a feature length behind-the-scenes documentary about the first film. It uses footage from the film's development, as well as stock footage from as far back as the production of Titanic in 1995. Also included are numerous interviews with cast, artists, and other crew members. The documentary was released as a bonus feature on the extended collector's edition of Avatar.

The documentary begins with a brief outline of Avatar and the art styles that were used, before moving right back to discuss James Cameron's experiences collecting small animals such as snakes and frogs as a child. Cameron stated that the idea for the film had been in his head in one form or another since then; it was not until he became influential in the film industry that he could even consider putting pen to paper on it though.

The film shoots ahead to 1995, with the development of Titanic well underway. It was then that he showed Jon Landau his initial scriptment, but the film was too visually complex for the then-available technology to keep up with. Also mentioned in this section was the short Cameron produced in 2001, Brother Termite, animating an alien character using motion capture. This is cited as one of the factors showing the progression of the technology, and that Avatar might be feasible.

Actual production did not begin until 2005. Scenes are shown from the ILM Prototype of Avatar, a test scene using Yunjin Kim as Neytiri. The documentary follows the development of the film, with Weta signing on in 2006 and the film being greenlit in 2007; it details the incredibly complex tools such as the virtual cameras that were used. It follows this process right up through the editing stage and the premiere in London.

The film the goes past the release to show the knock on effect worldwide, including scenes from James Cameron's appearance at Earth Day 2010, and the Belo Monte Dam protest. (also documented in A Message from Pandora) The film closes with comments from crew members from every field who worked on the film.